Should butalbital ever be given, much less to a pregnant woman?

Abstract

Butalbital is a barbiturate, most frequently prescribed in combination with acetaminophen or aspirin, and caffeine, for the treatment of migraine and tensiontype headaches.Its use has waned over the years, in part because so many better remedies are available, and in part because of its reputation for habituation, rapid development of medication overuse headache, and a potentially fatal withdrawal syndrome. This issue of Headache presents a case-controlled analysis of the associations between butalbital and a range of specific birth defects, mining data from the National Birth Defects Prevention study, which evaluates major birth defects across 10 states. Despite an analysis of 8373 unaffected controls and 21,090 case infants, it is an encouraging sign that only 73 case mothers and 15 control mothers reported periconceptional butalbital use. Of the 30 birth defect groups analyzed, statistical significance was found for 3 congenital heart defects: tetralogy of Fallot, pulmonary valve stenosis, and secundum-type atrial septal defect. The study is important despite its being underpowered by the lack of pregnant women using this barbiturate. Unfortunately, this medication is still a go-to drug for many prescribing doctors who mistakenly view it as safer than other alternatives. For those lacking prescription coverage, it is cheaper than many acute migraine treatments as well. There are many reasons never to prescribe any butalbital combination during pregnancy or any other time. Analyzing data from the American Migraine Prevalence and Prevention Study, Bigal et al wrote a seminal paper examining the comparative risk for transformation to medication overuse headache developing from varying acute migraine medications. The authors found that across all acute medication types, barbiturate compounds led the pack in transformation risk, with an odds ratio (OR) of 1.73 (95% confidence interval [CI] 1.10–2.73), beating out even opiates, which had an OR for transformation risk of 1.44 (95% CI 1.10–2.08).The probability of developing transformed or chronic migraine occurred with only 5 days of barbiturate use per month, a remarkably low frequency of use associated with chronification, and clearly the worst provoker of rebound among all the acute migraine treatment options evaluated. Butalbital compounds carry particular risk for habituation. The barbiturate ingredient has a much longer half-life than the caffeine and acetaminophen components. There are 2 risks. First, as the shorter half-life components wear off, the headache returns, and the individual with headache is then prompted to repeat the dose, before the barbiturate has cleared the system. Second, the analgesic half-life for butalbital is in the 4-6 hour range, while the pharmacokinetic elimination half-life is from 35-88 hours. The barbiturate builds up, and the individual inadvertently becomes habituated to the drug with increasing blood levels, putting the patient at risk. Monitoring butalbital usage has become increasingly difficult, as butalbital compounds have become easy to obtain over the internet. Prescription monitoring programs offered by many states may catch non-internet fills, but some of them do not routinely monitor butalbital compounds for reasons that are not clear. A cautionary tale of problems resulting from internet purchase of a butalbital, caffeine, and acetaminophen compound was related in startling detail in a case report published by Romero et al. A patient ISSN 0017-8748 doi: 10.1111/head.12208 Published by Wiley Periodicals, Inc. Headache © 2014 American Headache Society

DOI: 10.1111/head.12208

Cite this paper

@article{Tepper2014ShouldBE, title={Should butalbital ever be given, much less to a pregnant woman?}, author={Deborah E Tepper}, journal={Headache}, year={2014}, volume={54 1}, pages={10-1} }